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1.
为了解南四湖13条典型河流入湖口区的水质状况,本研究利用污染分担率值确定评价因子,并应用模糊数学改进层次分析法(IAHP)确定权重,同时求出各水质级别的模糊隶属函数并计算相应的隶属度,最后应用模糊综合评价法对其进行评价。结果表明:河流入湖口区的水质均较差,绝大多数属于Ⅳ类,TP和TN对水质的影响程度较大并远远超出发生富营养化的临界条件。梁济运河和城郭河入湖口区的水质甚至达到了Ⅴ类,泗河和韩庄运河入湖口区的水质较好,属于Ⅲ类,能够达到南水北调东线工程所规划的功能用水的水质要求。与2006至2011年的研究相比,TP、TN的平均含量总体上呈下降趋势,说明近年来南四湖流域环境监管力度成效显著。  相似文献   

2.
本文对2019年秋季江苏滨海北部近岸海域水质和沉积物环境进行了调查,分析研究结果表明:水质主要超标因子为化学需氧量、无机氮、活性磷酸盐、Cu、Pb和Cd;沉积物中As和硫化物超过第一类沉积物质量标准,但满足第二类海洋质量标准,其他指标均符合第一类沉积物质量标准。采用地累积指数法和潜在生态风险指数法进行评价,沉积物重金属除Cd外,潜在生态风险整体为低风险,单因子生态风险由高到低为Cd>Hg>As>Pb>Cu>Cr>Zn。  相似文献   

3.
本研究对2012~2013年大沽排污口沉积物中硫化物、有机碳、石油类以及7种重金属(铜、铅、锌、镉、总汞、砷和铬)等水质指标的监测数据进行统计,并对其中重要的水质指标进行水污染综合指数评估,旨在对海河水质进行较为系统的评价。结果显示,D3、D6、D7和D9四个站位水质属于Ⅱ和Ⅲ类标准,其余各站位均为Ⅰ类;其余各指标(TOC、TPH、Cu、Pb、Zn、Cd、Hg、As and Cr)的总体水平依次为Ⅰ、Ⅳ、Ⅱ、Ⅴ、Ⅱ、Ⅴ、Ⅲ、Ⅴ和Ⅴ类。各站位综合评价结果得到海河流域指数为3.28,说明海河流域处于严重污染状态,其污染程度超过该流域功能区的标准。  相似文献   

4.
<正>滨海地区是全球经济最发达、人类聚居密度最大的地区,滨海含水层中的地下水是这一地区重要的淡水资源。海水入侵到地下水中是由于天然或人类活动,使咸淡水之间的动态平衡被打破而出现海水向滨海淡水含水层入侵的现象。海水入侵将会导致(如水质恶化、土壤盐渍化及荒漠化等)一系列生态、环境恶化问题(成建梅等,2004)。滨海地区  相似文献   

5.
为保护涠洲岛珊瑚礁海洋公园的海洋环境,促进其海洋生态的可持续发展,文章根据2013—2017年该区9个站位的海洋环境监测数据,选取化学需氧量(COD)、石油类(Oil)、溶解氧(DO)、无机氮(DIN)和无机磷(DIP)5种海水因子,分别采用污染因子分类评价、单因子污染指数评价、有机污染指数评价和水质综合指数评价的方法,对海水因子的含量和分类以及海水水质进行评价。研究结果表明:各因子的平均含量大部分符合海水水质一类标准;COD和DIP未对海水环境造成污染,Oil从常态因子迅速上升为关键因子又逐渐下降为常态因子,DO从关键因子迅速下降为常态因子,DIN从常态因子迅速上升为关键因子;海水中DO超标,基本未受有机污染,水质整体状况为清洁。  相似文献   

6.
近几年海洋溢油事件频发,对滨海地区旅游环境造成了严重的污染。针对滨海旅游区的溢油现象进行定量评价,寻求合理的评价方案是当前相关领域专家学者普遍关注的问题。本文根据滨海旅游区生态系统的特性,以滨海旅游区的海水水质、岸滩环境和溢油危害为评价内容,构建滨海旅游区溢油污染评价指标体系和滨海旅游区溢油污染综合评价模型,并且基于GIS技术进行了系统架构设计与实现。通过模拟海洋溢油事件,对该系统进行了测试。测试结果表明:该系统能够对溢油区的污染等级做出快速评价。本研究为滨海旅游区的溢油污染评价提供了新的方法,该系统能够辅助相关部门管理溢油相关的综合信息,在溢油发生时快速反应,采取应急措施。  相似文献   

7.
滨海旅游资源评价指标体系的构建及应用——以厦门为例   总被引:1,自引:0,他引:1  
滨海旅游资源的研究是评价滨海地区旅游业发展的现状和潜力,使其更好地开发旅游资源,参与旅游产业竞争的重要依据。从自然资源、人文资源、资源协调性、开发与保育以及知名度5个方面共计39个因子构建滨海旅游资源开发利用与保育评价指标体系,通过运用层次分析法测算指标权重,并在此基础上结合问卷调查,以厦门市为例进行实证分析。结果表明,厦门滨海旅游资源总体良好。  相似文献   

8.
滨海湿地生态经济的综合评价模型   总被引:6,自引:4,他引:2  
通过对生态环境指标与社会经济指标两方面的分析,建立了滨海湿地生态经济的综合评价模型,定量计算了滨海湿地开发前总效益(V)、开发后总效益(V′)以及开发利用的限制因子(H)和评价因子(I),并以浙江省上虞市世纪丘围垦工程为例,对模型进行了验证计算,结果表明:(1)开发前后的大气调节、水文调节、污染物净化、提供生物栖息地等生态环境效益指标(Vee)和旅游休闲、科研教育、提供各种产品等经济效益指标(Vse)影响着对滨海湿地开发前后总效益以及开发可行性的判断;(2)当滨海湿地的开发评价因子I>1时〔I=V′/V=(Vee+′Vse)′/(Vee+Vse)〕,海涂开发后的总效益大于开发前的总效益,海涂开发具有可行性,否则为不宜开发;(3)当滨海湿地开发利用的限制因子H小于0.20时,应限制滨海湿地的开发、利用;(4)上虞市世纪丘海涂湿地的H为0.78,I为2.1,可见该海涂开发后,生态环境效益有所降低,但社会经济效益却大幅度地提高了,说明该海涂的开发是具有可行性的。  相似文献   

9.
通过土工试验和粒度分析,发现埕北海域沉积物主要以粉土和粉质黏土为主,局部地区分布有粉砂和淤泥质土。综合考虑研究区沉积物、水深地形、地貌、地质灾害等因素,可将研究区划分为4个工程区:Ⅰ区、Ⅱ区、Ⅲ区和Ⅳ区。针对4个工程区,采用模糊数学的方法,选择直接影响工程稳定性的5个主要因素即:沉积物类型、主要持力层埋深、主要持力层承载力、地形地貌和地质灾害类型作为评价因子定量对各区稳定性进行评价,发现4个工程地质区的稳定性分别为:Ⅰ区(稳定区)、Ⅱ区(不稳定区)、Ⅲ区(较不稳定区)和Ⅳ区(较稳定区)。以此为研究区的工程建设提供设计依据。  相似文献   

10.
根据 2 0 0 1年 2月和 7月对崎岖列岛附近海域的水质和底质表层沉积物调查结果 ,采用环境质量单项评价标准指数法 ,对该海域环境质量现状进行了评价与分析。结果表明 :(1 )该海域水质的 p H值、溶解氧和石油类等环境因子基本符合一类海水水质标准 ,化学需氧量、活性磷酸盐和无机氮浓度则超标严重 ,该海域水质已处于严重富营养化状态 (夏季比冬季富营养化程度略低 ) ;(2 )该海域底质表层沉积物中除部分站位的重金属 Cu、 Zn含量超标外 ,有机质、石油类和重金属 Pb、 Cd、 Hg的含量均未超标 ,底质环境状况尚好  相似文献   

11.
The analysis of the structure of the cryolithozone, facies, and thicknesses of the Quaternary sediments and the results of the physicochemical mathematical modeling of the modern shelf of the western part of the Laptev Sea support the influence of the Late Pleistocene glaciations on the heat conditions and the distribution of the permafrost in the area. A ~200-m thick glacier formed under aerial conditions from atmospheric precipitation represented the metamorphosed snow cover. According to the modeling, the long-living (from 60?50 to 10?4 ky) glacier reduced the thickness of the permafrost rocks in the reviewed shelf area for 280–360 m. The Holocene marine transgression additionally decreased the thickness from 50–140 m on the inner shelf to 220–350 m on the outer shelf. The modern submarine cryolithozone 450-0 m thick is wide-spread in the studied region from the coast to the shelf boundary (isobaths of 130–140 m), where it pinches out at a distance of ~380 km from the coast at a depth of ~250 m above the sea level.  相似文献   

12.
We analyze the components of the carbon system of the Sevastopol bay waters and the balance of main sediment-forming substances using the data of field investigations in 1998–2008. The interannual variations of total inorganic carbon and the equilibrium partial pressure of carbon dioxide in the bay water are noted. An increase in the flux of carbon dioxide into the bay and in the content of organic carbon in bottom sediments is revealed, and an explanation of this phenomenon is given. The priority accumulation of organic carbon in the sediments of the bay is established. We assess the interannual variation in the relative abundances of organic and inorganic carbon as an index of the carbon cycle stability.  相似文献   

13.
We generalize and analyze the state of investigations of the influence of river waters on the hydrologic structure of the Black Sea. Specific features of the water, regime and hydrography of rivers flowing into the sea, data on the discharge of rivers, and intrayear and interyear variability of the discharge are presented. We discuss and analyze works studying the transformation of river waters, routes of desalinized sea waters, and their influence on the thermohaline structure and dynamic regime of the sea. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

14.
We analyze the results of numerical calculations performed according to the three-dimensional interdisciplinary model of an ecological system of the Black-Sea shelf zone near the estuary of the Danube. The complete system of equations of hydrothermodynamics is solved together with transport equations of the advection-diffusion-reaction type used to describe the transformation of a substance (nitrogen) between the components of the characteristic vectors of the ecosystem: plankton, detritus, and biogenic elements (nitrates). We describe the distinctive features of the circumcontinental distribution of components obtained as a result of numerical experiments and present arguments for the conclusion that the ecosystem of the Danube estuary water area plays the role of a buffer zone between the press of the Danubian biogenic pollutions and the neighbouring areas of the shelf zone and open sea. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

15.
Ten years of semistationary studies of the interaction of the ice cover and the coastal relief of the Kandalakhsa Gulf in the White Sea allowed us to reveal the peculiarities of these processes in the warm and cold years and the mechanisms of the origination of ice forms, including ice tents, which govern the character of the tidal flats. Three dynamic fast ice zones are distinguished by their geomorphological location, morphology, and ice dynamics. The dependence of the mechanisms and volumes of the enrichment of the fast ice in the sediments on the coastal zone??s relief was established. At the coast of the Kindo Peninsula (Velikaya Salma Strait), the ice mostly contains fine-sandy sediments. Coarser sediments, including boulders, are occasional and frozen into the ice at the contact of the fast ice and the bottom. At the expense of the ice??s spreading by 4?C6 times in the warm years and 2?C4 times in the cold years, several thousand tons of sediments mostly from the tidal flat??s surface (100?C700 m3 from 1 km of coast in the wide tidal flats and <50 m3 on the steep coasts) are delivered to the water area.  相似文献   

16.
A relationship between paths of the Kuroshio and Kuroshio Extension (KE) is investigated, using the satellite-derived altimetry dataset of 1993–2008. When the Kuroshio takes the nearshore nonlarge meander path or typical large meander path and resultantly goes through the deeper channel (about 2500 m) of the Izu-Ogasawara Ridge, the KE path adopts a relatively stable state with the two quasi-stationary meanders. On the other hand, when the Kuroshio takes the offshore nonlarge meander path and then passes over the shallower part of the Ridge (about 1000 m), the KE path tends to be convoluted, i.e., an unstable state.  相似文献   

17.
We use many-year archival observations of hydrologic and hydrobiologic state of the Sea of Azov for the identification of the structure of a model of its ecosystem. The ecosystem model, supplemented with expert estimates of bioresource consumption (fish reserve), contamination level, and possible ecologic fines for violation of the sea natural state, is formalized by the method of system dynamics. Hereat, the major part of influence functions is found in terms of observational data with application of self-organization algorithms. We also present the results of simulated experiments with the model of the ecosystem, which enable us to analyse scenarios of its behaviour under the influence of various external factors (wind, river discharge, water exchange with the Black Sea, etc.). Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

18.
Three mathematical models are considered: a two-dimensional model for calculating the concentration fields of the ecosystem components on the shelf of the Republic of Guinea, a pointwise model for the annual variation of the components, and a two predators-prey model. These models are used to study the effect of hydrodynamic conditions on the state of the shelf ecosystem and for research into the causes which distort the balance between marketable and unmarketable fish.Translated by Mikhail M. Trufanov.  相似文献   

19.
The first data on the temporal evolution of the slope of the buried depression of the Black Sea are obtained. The sharp change in the rate of the decrease in the slope steepness that occurred in the Late Miocene-Pliocene time reflects a reorientation of the vector of mutual movement and a related intensification of the collision between the Arabian and Eurasian lithospheric plates.  相似文献   

20.
The stages of the development of the basin of the Bransfield Strait   总被引:1,自引:0,他引:1  
The study of the sedimentary body of the Bransfield Strait has made it possible to identify several sedimentary complexes, to construct the first electronic charts for the acoustic basement, and to establish four stages of the evolution of its floor, which updates the previous knowledge about the formation of the strait. At the first stage, there was an increase in tension stresses that were accompanied by the local splits of the continental crust at the periphery of the Antarctic Peninsula. At the second stage, a graben-like structure filled with the Lower stratigraphic complex was formed northward of the Antarctic Peninsula. At the third stage, the continuing processes of extension led to intensive explosive activity of the growing volcanic structures and filling of the graben with sediments of the Middle seismostratigraphic complex. The fourth stage, which has continued until recently, is characterized by quasi-linear localization of the major centers of volcanic activity in the band closer to the South-Shetland Islands and the formation of the Upper seismostratigraphic sedimentary complex. The evolution of the floor of the Bransfield Strait reflects the process of penetration of the American-Antarctic ridge to the continental lithosphere of the Antarctic Peninsula for the last million years.  相似文献   

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